1. Technical Field
The invention relates to intermediate deck structures for use in transport vehicles such as trucks and trailer vans, railway cars, freight containers and the like, and more particularly, to a foldable deck for use in such vehicles.
2. Description of Related Art
In a typical truck van, a horizontal bed or floor is provided for supporting articles being transported. Articles are placed on this bed, and depending upon the size of the articles, they may be stacked upon each other at two or more levels.
In some instances, it may be impractical to stack the articles due to the weight or configuration. Where this is the case, a substantial amount of the vehicle interior is rendered unusable. For example, where the articles or containers are fragile, damage to the articles will occur if stacked to the extent that the weight of the upper articles would damage lower articles. In those instances, it is often necessary to avoid stacking or to minimize the amount of stacking.
Further, to maximize volume capacity of transporting small to medium sized freight and to reduce the risk of crushing packages, shipping companies have sought to add shelves inside tractor trailers. The shelf span is from wall to wall and separates the trailer volume into spaces below and above the shelf.
Some articles are also somewhat difficult to handle due to their weight and configuration. This creates problems for the individuals loading the articles on a bed. Thus, even if articles at a lower level will not be damaged when other articles are stacked thereon, stacking itself may be quite cumbersome and inefficient due to the size and weight of the articles.
To facilitate loading and unloading the shelf-equipped trailer, the shelf can be divided into approximately two foot-wide sections and be designed to fold up against the wall. As cargo is loaded into the trailer from the front to the rear, each shelf section is individually folded down away from the wall and loaded with cargo. Various types of collapsible or removable intermediate deck structures have been proposed for supporting freight articles of various shapes and weights above the horizontal bed or floor of a transport van, and the like, in order to increase the load carrying ability of a van and to maximize the use of the available cubic capacity of a van. Such attempts of using intermediate decks in vehicles are discussed by U.S. Pat. Nos. 6,585,306, 6,854,400, 5,452,972, and 3,911,832.
The use of collapsible or removable intermediate decks has not met with wide success, however, due to inefficiencies in the design of the decks which make them too complex, too expensive for practical purposes, or simply too inconvenient to use.
As discussed in U.S. Pat. No. 6,585,306, the design of existing intermediate deck structures often consist of two deck panels, hinge mounted on opposing walls to enable storage of the deck panels vertically against the side walls. The deck panels rotate downwardly or upwardly on the hinges to a horizontal position to form a continuous section of deck, or secondary floor. Typically, this form requires a means of supporting the deck halves horizontally in a manner which both encroaches on additional usable volume for loading the freight or cargo, and interferes with that space requiring extra effort and time to load around it. Such supports include cantilever support structures, suspension chains or cables or even vertical support legs extending to the primary floor.
One problem with prior art solutions is that they fail to provide the necessary ergonomic features required when changing from a secure, upright position into an extended horizontal position. For example, it is highly desirable, for safety concerns that pinch points be minimized or eliminated to prevent the accidental severing of a finger. Hence, deck panels using slidable members to engage and lock deck panels together are undesirable. Similarly, deck panels using latch-type devices that can provide a pinch point are undesirable. Further, human movement required to change the position of the deck should minimize hand and arm movements above the shoulders and below the waist to reduce or eliminate potential back injury.
Consequently, there is a need for a system for supporting articles for transportation purposes. In particular, there is a need for such a support system that is of a highly efficient design whereby the deck can be economically installed in a vehicle and the system can be safely, efficiently, and ergonomically operated by a single user.